The Seven Great Demon Lords are the chief nobility of the Dark Area, and each member has the right to command legions of the "Nightmare Soldiers", if they so wish.[4] They are also able to subvert the cycle of reincarnation presided over by Anubimon; instead of having the chance to be reborn, the data of their victims becomes their own flesh and blood.[5] Despite their might, certain other demonic Digimon, such as GranDracmon, are powerful enough to stand outside their authority.[6]

Crests

Each of the Seven Great Demon Lords possesses a unique "Crest" (紋章,Monshou?)[8] displayed in one of the seven colors of the visible spectrum. Each depicts one of the seals of the "Seven Olympian Spirits", a group of mythological entities who, under God, ruled over the 196 provinces of Heaven and presided over the natural world for 490 years each.[9] Each Olympian Spirit is associated with a heavenly body, also depicted on the Crest.

Within the space between the two concentric circles is text stating a designated Level (this is "666" for all the crests, a reference to the "Number of the Beast" mentioned in the Book of Revelation), System (the demon that traditionally represents the Demon Lord's respective sin), and Code (the Demon Lord's respective sin). At the bottom of the inner circle is text which specifies a caution for a Purgatory Level ranging between 1 and 7, corresponding to the arrangement of Purgatory within Dante Alighieri's La Divina Commedia.

The structure of the text is in the following format:

LEVEL:___ SYSTEM:___ CODE:___ (repeated twice)

CAUTION! PURGATORY LEVEL ___

Crown of the Seven Deadly Sins

The Crown of the Seven Deadly Sins (７つの大罪の冠,Nanatsu no Daizai no Kanmuri?) is composed of all seven Crests arranged in an array, and is worn by both Super Demon Lords, Lucemon Shadowlord Mode and Ogudomon.

Code Key

The Code Keys (コードキー,Kōdo Kī?) are mystical cards which appear in Digimon World Data Squad. Each of the seven cards is can be used to transform a child exhibiting a deadly sin into the Demon Lord matching the Crest depicted on the card. The DigiCode on the back of each Code Key reads "THE SEVEN GREAT DEMON LORDS" () and "THE SEVEN DEADLY SINS" (), while the front of the card is unique for each code key, and is structured in the following format, also written in DigiCode:

DIGIMON NAME

(CREST)

DIGIMON NAME:SIN

SPECIAL MOVE 1

SPECIAL MOVE 2

SPECIAL MOVE 3

"LUCEMON FM" and "DAEMON" are used for Lucemon and Creepymon, respectively.

Gate of Deadly Sins

The Gate of Deadly Sins

The Gate of Deadly Sins (大罪の門,Daizai no Mon?) is engraved with seals depicting the Crests of the Seven Deadly Sins.

Tower of the Seven Deadly Sins

The Towers of the Seven Deadly Sins (七大罪の塔,Nanadaizai no Tou?) are mysterious buildings that appear in Digimon Collectors. Once they begin appearing across the Digital World, they attract Digimon exhibiting their respective sin, as well as the Protagonist, who is sent to investigate them by the Royal Knights. Although the protagonist defeats the Demon Lords lurking within each tower, this only serves to bring about the manifestation of Ogudomon's tower, as well as the Super Demon Lord itself.

Belphemon

Before the events of the series, Akihiro Kurata discovered a temple, inside he found a door bearing the Crest of Courage, upon entering he found a chest containing a Digi-Egg that would later hatch and digivolve into Belphemon Sleep Mode. Kurata then began a campaign to revive Belphemon by collecting "Digimon life energy", and thereby conquer both the human world and the Digital World—a task he succeeds at by destroying and collecting the life energy of the massive ElDradimon.

Believing he has successfully brought Thomas H. Norstein to his cause, Kurata uses the "Digimon control device" Thomas had made for him to command Belphemon. However, during Belphemon's attack, Thomas double-crosses Kurata, and destroys the control device, forcing Kurata to make another gambit. He seemingly transforms himself into data and merges with Belphemon, taking control over the Digimon's body and transforming it into Belphemon Rage Mode.

Soon after, Thomas comes to join the fight, with Marcus Damon on his way as well. MirageGaogamon faces off against Belphemon only to be stomped on. He might have been finished if Rosemon hadn't seized Belphemon's arm. Belphemon Rage Mode blocks the attacks shot by Rosemon and defeats Crowmon, who reverts back to Falcomon. Through Keenan Crier's rage, Falcomon double warp digivolves to Ravemon and attacks Belphemon but is unable to do anything more than anger him. Belphemon launches an attack at Marcus and Thomas, which Ravemon blocks. Due to his increasing anger, Kurata loses control to Belphemon's true conciousness as he is in "Rage Mode". Unlike Kurata, Belphemon's only goal is destruction. Marcus's Digi-Egg hatches and digivolves from Koromon to Agumon.

Once Agumon digivolves into ShineGreymon, Kurata's face emerges from Belphemon's chest. He then drains electricity from the city to cause Belphemon Rage Mode to grow and swallow a number of space oscillation devices to give it the power to tear rifts between both worlds, threatening to bring both worlds crashing together. He defeats RookChessmon and BishopChessmon, who revert back to the two PawnChessmon. ShineGreymon digivolves into Burst Mode and destroys Belphemon Rage Mode, with help from Marcus' D.N.A. going straight through Belphemon Rage Mode's chest, where Kurata's face is.

Despite the fact that, normally, Belphemon's Sleep Mode is not considered a member, the voice over for Belphemon Sleep Mode includes it as one.

Digimon World Data Squad

The "Mao Digimon" are created when one of the Code Keys of the Seven Deadly Sins is merged with a person who exhibited the respective sin. However, they can be destroyed with enough hard work before they can fully regain their strength.

During a series of Digimon attacks, earthquakes, and disappearances, the Mao Digimon reveal themselves with an attack from Creepymon. Five of them, Belphemon, Barbamon, Lilithmon, Beelzemon, and Leviamon, are quickly defeated, releasing their respective Code Keys and the children they were each made from; Lilithmon is revealed to be created from Yuma Kagura, the little sister of one of DATS's researchers, Tsukasa Kagura. Meanwhile, a private investigator named Kosaburo Katsura and his Digimon Biyomon attempt to steal the Code Keys.

After Leviamon is defeated, Tsukasa appears and reveals that he is behind both Kosaburo and the Mao Digimon; he wants to release Lucemon in order to become the strongest Tamer, and had his henchmen DemiDevimon kidnap the children and transform them into the Mao Digimon, while Creepymon would take the Code Keys of the defeated Mao Digimon to apply to Lucemon's seal.

After a defeat in the Doomsday Forest, Creepymon attack DATS Headquarters and is defeated again. Manami Nitta, a young girl, runs up to the dying Creepymon, and he releases his human, who is revealed to be Manami's father and a lost DATS member named Masaki Nitta. Kagura had told Creepymon that the only way to return home to the Real World was to retrieve the Code Keys and release the seal on Lucemon. He reveals that Kagura already has the Code Key of Wrath. As Thomas realizes that Creepymon's attack was merely a distraction to give Kagura time to release the seal, Masaki begins to dissipate; he had spent too much time as Creepymon, and was no longer anything more than data.

Kagura finally releases Lucemon, who fights DATS but is defeated. However, its defeat proves to be a farce as Lucemon quickly revives himself and turns Kagura into the Code Key of Pride, and absorbs him; while the first six Code Keys would free Lucemon from his seal in the Dark Area, the Code Key of Pride allows him to leave the Dark Area entirely. Although Lucemon is defeated once again, he transforms into the terrifying "Cho-Mao". Despite this form's overwhelming power, DATS manages to defeat him as well, freeing an ashamed and repentant Kagura and ending the Mao Digimon crisis. However, the cards still exist and the data of the Mao digimon has not yet been deleted.

After the main story, the Mao Digimons' lingering DATA can be encountered where they were defeated. Upon meeting the DATS team again, they pick a fight with one of the group who displays one of the seven sins. Agumon obtains Belphemon's power; Lalamon gains Lucemon's; Gaomon gains Barbamon's; Falcomon gains Leviamon's; Biyomon gains Beelzemon's; Renamon gains Lillithmon; and Creepymon gives him to Agumon without a fight. This encounters allows that Digimon who gained the Mao's power to digivolve into their form once the right amount of different digimon types are defeated.

Lucemon

As the Cho-Mao (超魔王,Chō Maō?, lit. "Super Demon Lord"), leader of all the other Mao Digimon, it takes all six of the other Code Keys to release Lucemon from his seal in the Ice Caverns. He used his dark powers to manipulate Tsukasa Kagura's bitterness towards Thomas to have him begin a quest to retrieve the Code Keys from his fellow Mao Digimon's data to free him from imprisonment, all the while making him think he was in charge of the evil Digimon working for him. Upon being unsealed and given a DigiSoul Charge from Kagura, Lucemon proceeded to fight the DATS team, but lost. Seeing that he needed to gain more power from the Dark Area, Lucemon betrays Kagura by turning him into the Code Key of Pride and absorbing him to gain freedom from the Digital World. Confronting the DATS team again, Lucemon digivolves to the Demon Lord form, the final boss, only to be defeated once more.

Attacks

As Lucemon Chaos Mode

Paradise Lost : Causes a powerful explosion of red energy.

Dead or Alive : Deals damage based on a clock's roullete result.

Deadly Roll

Terrible Dance: Performs a spin kick.

As Demon Lord

Dimension Slasher: Slashes the enemy and turns the Digimon into Digi-Eggs.

Purgetorial Flame: Summons the seven crests of the Mao digimon, sending out a powerful blast of fire.

Creepymon

Creepymon first appears and defeats Marcus Damon and Agumon at Walter Island, after the pair defeat Tylomon. While overlooking the sealed Lucemon, it meets Tsukasa Kagura, who promises to give it a portal to the Real World. It later encounters the DATS team in Doomsday Forest Ruins, where they beat it. However, Kagura keeps his end of the bargain and by using five of the Code Keys, breaks down the barrier between the two worlds enough for it and other dangerous Digimon to leave. In the real world, it tries making contact with former DATS member Misaki Nitta's daughter, who sees that he is within the evil Digimon. However, a final battle between Creepymon and the DATS team frees Nitta from him, but at a heavy cost. Not only did he give the "Code Key of Wrath" to Kagura, he is not able to return to normal because he was Creepymon for an extended point of time, remaining as data fragments in the Digital World.

Attacks

Flame Inferno : A powerful blast of fire.

Chaos Flare : A more powerful blast of fire.

Double Dust: Slams fists over target's head.

Belphemon

Belphemon is the boss of the Rage Caverns and was created from a missing boy and a "Code Key of Sloth" card. After the DATS team defeat him, the boy and card return to normal. Belphemon was responsible for sizemic activity that the DATS team felt during their search for him.

Lilithmon

Lilithmon is the boss of Livilus Island. Lilithmon is created from Yuma Kagura and the "Code Key of Lust" card. Befitting the sin that created her, Lillith on seeks to flirt with men. She insults and then fights Yoshino, but after the DATS team defeats her, Yuma and the card return to normal.

Attacks

Phantom Pain : Blows a kiss, which causes the target internal damage.

Darkness Love : Puts the target until a spell that makes one love her.

Nazar Nail : Strikes target with poion nails.

Evil Sigh : Puts tartget to sleep.

Digimon World DS

After getting the final quest, the Seven Great Demon Lords send the protagonist a message to challenge the Tamer King to a fight before they destroy the Digital World. The protagonist is invited to a battle by each of them in turn, and each time one of the Demon Lords is defeated, a new area is unlocked. In the end, the protagonist is challenged to fight them each in a row without breaks, and each of them are destroyed after these battles. After the last Demon Lord disappears, Beelzemon manages to reappear, reformed of its evil ways, and gives itself to the protagonist as scan data.

Lucemon Chaos Mode

Lucemon Chaos Mode first appears at Core Field at level 75, then at Destroyed Belt.

Leviamon

Leviamon is fought in the Demon Lord quest at the Undersea Drive, and again at Destroyed Belt.

Daemon

Daemon must be defeated by the player as part of the quest to defeat the Seven Great Demon Lords, and is the first Demon Lord that the player fights. The fight happens at the Hard Mountains, and then at Destroyed Belt.

Belphemon Rage Mode

Belphemon is one of the final bosses in Digimon World DS. After defeating the first Demon Lord, Belphemon challenges the player by luring him/her into the final domain, where he and the other Demon Lords ambush the player. When the first six fall in battle, Belphemon will personally fight the player. He appears as the strongest Demon Lord and the strongest unobtainable boss or even the strongest Digimon in the game.

Barbamon

Barbamon appears first at Lava River, then at Destroyed Belt.

Beelzemon

Beelzemon appears first at Sky Palace, and then at Destroyed Belt. He is the second Demon Lord that the player fights. He is also the only obtainable Digimon that is a member of the Demon Lords, obtaining a 100% data scan of him and Calumon's after completing Quest 60. Then, any Infermon can digivolve into Beelzemon.

Lilithmon

Lilithmon appears first at Tropical Isles at Level 75, then at Destroyed Belt at Level 99.

Digimon Next

Barbamon

Barbamon is the Demon Lord who has taken over the Host Computer Yggdrasill in the System World, where he now makes his base. He aims to take over the Digital World by obtaining all the DigiMemories for the future of Digimon, NEO, already having the Dark DigiMemory. For that purpose, he creates the Commandments and recruits Shou Kahara and Peckmon, who have the Bird DigiMemory.

As a member of the Seven Great Demon Lords, he forces himself into System World and confronts Yggdrasill on the policies of "Art" Digimon, Digimon born with Tamers. Upon deciding that revolution is in order, Barbamon merges with Yggdrasill and became the host computer itself. He fights Tsurugi Tatsuno but is killed when VictoryGreymon destroys him. His last act is to give his gathered DigiMemories to NEO, giving him consciousness.

Barbamon appears one last time when the other DigiMemory holders restrain NEO; his Dark DigiMemory imprinted with his consciousness gives NEO the ability to attack Tsurugi and Yuu Inui, only to have his own Commandments turn on him.